[1] Ewha Womans Univ, Seoul Hosp, Coll Med, Dept Emergency Med, 260 Gonghang Daero, Seoul 07804, South Korea
[2] Ewha Womans Univ, Mokdong Hosp, Coll Med, Dept Emergency Med, 1071 Anyangcheon Ro, Seoul, South Korea
[3] Chung Ang Univ, Dept Emergency Med, Coll Med, Gwangmyeong Hosp, 110 Deokan Ro, Seoul, Gyeonggi Do, South Korea